<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>减少数据读取次数</title>
</head>
<body>
  <div id="skip" class="skip"></div>
  <script>
    var oBox = document.getElementById('skip')
    function hasEle (ele, cls) {
      return ele.className == cls
    }

    function hasEle (ele, cls) {
      var clsname = ele.className
      return clsname == cls
    }
    console.log(hasEle(oBox, 'skip'))
  </script>
</body>
</html>